[[def_detached_HEAD]]detached HEAD::
Normally the <<def_HEAD,HEAD>> stores the name of a
- <<def_branch,branch>>. However, Git also allows you to <<def_checkout,check out>>
- an arbitrary <<def_commit,commit>> that isn't necessarily the tip of any
- particular branch. In this case HEAD is said to be "detached".
+ <<def_branch,branch>>, and commands that operate on the
+ history HEAD represents operate on the history leading to the
+ tip of the branch the HEAD points at. However, Git also
+ allows you to <<def_checkout,check out>> an arbitrary
+ <<def_commit,commit>> that isn't necessarily the tip of any
+ particular branch. The HEAD in such a state is called
+ "detached".
++
+Note that commands that operate on the history of the current branch
+(e.g. `git commit` to build a new history on top of it) still work
+while the HEAD is detached. They update the HEAD to point at the tip
+of the updated history without affecting any branch. Commands that
+update or inquire information _about_ the current branch (e.g. `git
+branch --set-upstream-to` that sets what remote tracking branch the
+current branch integrates with) obviously do not work, as there is no
+(real) current branch to ask about in this state.
- [[def_dircache]]dircache::
- You are *waaaaay* behind. See <<def_index,index>>.
-
[[def_directory]]directory::
The list you get with "ls" :-)
it contains modifications which have not been <<def_commit,committed>> to the current
<<def_branch,branch>>.
- [[def_ent]]ent::
- Favorite synonym to "<<def_tree-ish,tree-ish>>" by some total geeks. See
- http://en.wikipedia.org/wiki/Ent_(Middle-earth) for an in-depth
- explanation. Avoid this term, not to confuse people.
-
[[def_evil_merge]]evil merge::
An evil merge is a <<def_merge,merge>> that introduces changes that
do not appear in any <<def_parent,parent>>.
created. Configured via the `.git/info/grafts` file.
[[def_hash]]hash::
- In Git's context, synonym to <<def_object_name,object name>>.
+ In Git's context, synonym for <<def_object_name,object name>>.
[[def_head]]head::
A <<def_ref,named reference>> to the <<def_commit,commit>> at the tip of a
[[def_object]]object::
The unit of storage in Git. It is uniquely identified by the
- <<def_SHA1,SHA1>> of its contents. Consequently, an
+ <<def_SHA1,SHA-1>> of its contents. Consequently, an
object can not be changed.
[[def_object_database]]object database::
Synonym for <<def_object_name,object name>>.
[[def_object_name]]object name::
- The unique identifier of an <<def_object,object>>. The <<def_hash,hash>>
- of the object's contents using the Secure Hash Algorithm
- 1 and usually represented by the 40 character hexadecimal encoding of
- the <<def_hash,hash>> of the object.
+ The unique identifier of an <<def_object,object>>. The
+ object name is usually represented by a 40 character
+ hexadecimal string. Also colloquially called <<def_SHA1,SHA-1>>.
[[def_object_type]]object type::
One of the identifiers "<<def_commit_object,commit>>",
<<def_object,object>>.
[[def_octopus]]octopus::
- To <<def_merge,merge>> more than two <<def_branch,branches>>. Also denotes an
- intelligent predator.
+ To <<def_merge,merge>> more than two <<def_branch,branches>>.
[[def_origin]]origin::
The default upstream <<def_repository,repository>>. Most projects have
pack.
[[def_pathspec]]pathspec::
- Pattern used to specify paths.
+ Pattern used to limit paths in Git commands.
+
Pathspecs are used on the command line of "git ls-files", "git
ls-tree", "git add", "git grep", "git diff", "git checkout",
worktree. See the documentation of each command for whether
paths are relative to the current directory or toplevel. The
pathspec syntax is as follows:
+ +
+ --
* any path matches itself
* the pathspec up to the last slash represents a
of the pathname. Paths relative to the directory
prefix will be matched against that pattern using fnmatch(3);
in particular, '*' and '?' _can_ match directory separators.
+
+ --
+
For example, Documentation/*.jpg will match all .jpg files
in the Documentation subtree,
including Documentation/chapter_1/figure_1.jpg.
-
+
A pathspec that begins with a colon `:` has special meaning. In the
short form, the leading colon `:` is followed by zero or more "magic
against the path.
+
The "magic signature" consists of an ASCII symbol that is not
- alphanumeric.
- +
- --
- top `/`;;
- The magic word `top` (mnemonic: `/`) makes the pattern match
- from the root of the working tree, even when you are running
- the command from inside a subdirectory.
- --
- +
- Currently only the slash `/` is recognized as the "magic signature",
- but it is envisioned that we will support more types of magic in later
- versions of Git.
+ alphanumeric. Currently only the slash `/` is recognized as a
+ "magic signature": it makes the pattern match from the root of
+ the working tree, even when you are running the command from
+ inside a subdirectory.
+
A pathspec with only a colon means "there is no pathspec". This form
should not be combined with other pathspec.
to the result.
[[def_ref]]ref::
- A 40-byte hex representation of a <<def_SHA1,SHA1>> or a name that
+ A 40-byte hex representation of a <<def_SHA1,SHA-1>> or a name that
denotes a particular <<def_object,object>>. They may be stored in
a file under `$GIT_DIR/refs/` directory, or
in the `$GIT_DIR/packed-refs` file.
[[def_refspec]]refspec::
A "refspec" is used by <<def_fetch,fetch>> and
<<def_push,push>> to describe the mapping between remote
- <<def_ref,ref>> and local ref. They are combined with a colon in
- the format <src>:<dst>, preceded by an optional plus sign, +.
- For example: `git fetch $URL
- refs/heads/master:refs/heads/origin` means "grab the master
- <<def_branch,branch>> <<def_head,head>> from the $URL and store
- it as my origin branch head". And `git push
- $URL refs/heads/master:refs/heads/to-upstream` means "publish my
- master branch head as to-upstream branch at $URL". See also
- linkgit:git-push[1].
+ <<def_ref,ref>> and local ref.
[[def_remote_tracking_branch]]remote-tracking branch::
A regular Git <<def_branch,branch>> that is used to follow changes from
[[def_SCM]]SCM::
Source code management (tool).
- [[def_SHA1]]SHA1::
- Synonym for <<def_object_name,object name>>.
+ [[def_SHA1]]SHA-1::
+ "Secure Hash Algorithm 1"; a cryptographic hash function.
+ In the context of Git used as a synonym for <<def_object_name,object name>>.
[[def_shallow_repository]]shallow repository::
A shallow <<def_repository,repository>> has an incomplete
its history can be later deepened with linkgit:git-fetch[1].
[[def_symref]]symref::
- Symbolic reference: instead of containing the <<def_SHA1,SHA1>>
+ Symbolic reference: instead of containing the <<def_SHA1,SHA-1>>
id itself, it is of the format 'ref: refs/some/thing' and when
referenced, it recursively dereferences to this reference.
'<<def_HEAD,HEAD>>' is a prime example of a symref. Symbolic